Tampilkan postingan dengan label Guy McPherson. Tampilkan semua postingan
Tampilkan postingan dengan label Guy McPherson. Tampilkan semua postingan

Jumat, 18 Juli 2014

Smoke Blankets North America


A thick layer of smoke blankets large parts of North America, as also illustrated by the animation below based on images from July 15 to 18, 2014, from Wunderground.com.

[ note that this animation is a 2.3MB file that may take some time to fully load ]
The are also extensive wildfires throughout the boreal forest and tundra zones of Central Siberia in Russia.

Such wildfires can send huge amounts of carbon dioxide, methane, soot, dust and volatile organic compounds into the atmosphere. Much of this gets deposited at higher latitudes, discoloring land, snow and ice, and thus speeding up warming by absorbing more sunlight that was previously reflected back into space.

Soils at higher latitudes can contain huge amounts of carbon in the form of peat, as described in the earlier post The Threat of Wildfires in the North. There are further conditions that make the situation in the Arctic so dangerous.
Temperature anomaly March-April-May-June 2014 (JMA)

The Arctic is particularly vulnerable to warming due to geographics. Seas in the Arctic Ocean are often shallow and covered by sea ice that is disappearing rapidly. Largely surrounded by land that is also rapidly losing its snow and ice cover, the Arctic Ocean acts like a trap capturing heat carried in by the Gulf Stream, which brings in ever warmer water. Of all the heat trapped on Earth by greenhouse gases, 90% goes into oceans, while a large part of the remaining 10% goes into melting the snow and ice cover in the Arctic, as described in an earlier post. Such basic conditions make that the Arctic is prone to warming.

Then, there are huge amounts of methane held in sediments under the Arctic Ocean, in the form of hydrates and free gas. Unlike methane releases from biological sources elsewhere on Earth, methane can be released from the seafloor of the Arctic Ocean in large quantities, in sudden eruptions that are concentrated in one area.

Until now, permafrost and the sea ice have acted as a seal, preventing heat from penetrating these methane hydrates and causing further destabilization. As long as there is ice, additional energy will go into melting the ice, and temperatures will not rise. The ice also acts as a glue, keeping the soil together and preventing hydrate destabilization from pressure changes and shockwaves resulting from seismic activity. Once the ice is gone, sediments become prone to destabilization and heat can more easily move down along fractures in the sediment, reaching hydrates that had until then remained stable.
 
Temperature anomaly March-April-May 2014 (NASA)
When methane escapes from the seafloor of the Arctic Ocean and travels through waters that are only shallow, there is little opportunity for this methane to be broken down in the water, so a lot of it will enter the atmosphere over the Arctic Ocean. The Coriolis effect will spread the methane sideways, but latitudes over the Arctic are relatively short, making the methane return at the same spot relatively quickly, while the polar jet stream acts as a barrier keeping much of the methane within the Arctic atmosphere. In case of large methane eruptions, the atmosphere over the Arctic will quickly become supersaturated with methane that has a huge initial local warming potential.

Hydroxyl levels in the atmosphere over the Arctic are very low, extending the lifetime of methane and other precursors of stratospheric ozone and water vapor, each of which have a strong short-term local warming potential. In June/July, insolation in the Arctic is higher than anywhere else on Earth, with the potential to quickly warm up shallow waters, making that heat can penetrate deep into sediments under the seafloor.

created by Sam Carana, part of AGU 2011 poster
The initial impact of this methane will be felt most severely in the Arctic itself, given the concentrated and abrupt nature of such releases, with the danger that even relatively small releases of methane from the seafloor of the Arctic can trigger further destabilization of hydrates and further methane releases, escalating into runaway warming.

This danger is depicted in the image on the right, showing how albedo changes and methane releases act as feedbacks that further accelerate warming in the Arctic, eventually spiraling into runaway global warming.

The currently very high sea surface temperature anomalies are illustrated by the two images below.




As the image below right shows, sea surface temperatures as high as 18 degrees Celsius (64.4 degrees Fahrenheit) are currently recorded in the Arctic.

Albedo changes and methane releases are only two out of numerous feedbacks that are accelerating warming in the Arctic.

Also included must be the fact that Earth is in a state of energy imbalance. Earth is receiving more heat from sunlight than it is emitting back into space. Over the past 50 years, the oceans have absorbed about 90% of the total heat added to the climate system, while the rest goes to melting sea and land ice, warming the land surface and warming and moistening the atmosphere.

In a 2005 paper, James Hansen et al. estimated that it would take 25 to 50 years for Earth’s surface temperature to reach 60% of its equilibrium response, in case there would be no further change of atmospheric composition. The authors added that the delay could be as short as ten years.

Earth's waters act as a buffer, delaying the rise in land surface temperatures that would otherwise occur, but this delay could be shortened. Much of that extra ocean heat may enter the atmosphere much sooner, e.g. as part of an El NiƱo event. Another buffer, Arctic sea ice, could collapse within years, as illustrated by the image below.

[ click on image to enlarge ]
The demise of sea ice comes with huge albedo changes, resulting in more heat getting absorbed by the Arctic Ocean, in turn speeding up warming of the often shallow waters of the Arctic Ocean. This threatens to make heat penetrate subsea sediments containing huge amounts of methane. Abrupt release of large amounts of methane would warm up the Arctic even more, triggering even further methane releases in a spiral of runaway warming.

Particularly worrying is the currently very warm water that is penetrating the Arctic Ocean from the Atlantic Ocean and also from the Pacific Ocean, as illustrated by the image further above and the image on the right.

The danger is that the Arctic will warm rapidly with decline of the snow and ice cover that until now has acted as a buffer absorbing heat, with more sunlight gets absorbed due to albedo changes and as with additional emissions, particularly methane, resulting from accelerating warming in the Arctic.

The numerous feedbacks that accelerate warming in the Arctic are pictured in the image below.

[ from: climateplan.blogspot.com/p/feedbacks.html ]
Furthermore, the necessary shift to clean energy will also remove the current masking effect of aerosols emitted when burning fuel. One study finds that a 35% – 80% cut in people's emission of aerosols and their precursors will result in about 1°C of additional global warming.

In the video below and the video further down below, Guy McPherson discusses Climate Change and Human Extinction.





This is further illustrated by the image below, showing how surface temperature rises are accelerating in the Arctic compared to global rises, with trendlines added including one for runaway global warming, from How many deaths could result from failure to act on climate change?
[ click on image to enlarge ]
The situation is dire and calls for comprehensive and effective action, as discussed at the Climate Plan blog.

Hat tip to Jim Kirkcaldy for pointing at the wildfire development at an early stage.

Kamis, 06 Maret 2014

Presentation by Guy McPherson

Presentation by Guy McPherson, February 2014, Traditions Cafe, Olympia WA.



View the video of the presentation below:





Related

- Tour by Guy McPherson along the coasts of Oregon and Washington
http://guymcpherson.com/2014/03/presenting-in-olympia-washington

- Earth is on the edge of runaway warming
http://arctic-news.blogspot.com/2013/04/earth-is-on-the-edge-of-runaway-warming.html

- Arctic Methane Impact
http://arctic-news.blogspot.com/2013/11/arctic-methane-impact.html

- CO2 growth highest on record
http://arctic-news.blogspot.com/2014/02/co2-growth-highest-on-record.html





Senin, 28 Oktober 2013

How Do We Act in the Face of Climate Chaos?

Guy McPherson


Guy R. McPherson is Professor Emeritus of Natural Resources
and 
Ecology & Evolutionary Biology at University of Arizona.
Below are some (slighly edited) extracts from a post at Guy
McPherson's website: 
summary and update on climate change.




The Warning

As described by the United Nations Advisory Group on Greenhouse Gases in 1990, temperature rise “beyond 1 degree C may elicit rapid, unpredictable and non-linear responses that could lead to extensive ecosystem damage”.

We’ve clearly triggered the types of positive feedbacks the United Nations warned about in 1990. Yet my colleagues and acquaintances think we can and will work our way out of this horrific mess with permaculture (which is not to denigrate permaculture, the principles of which are implemented at the mud hut). Reforestation doesn’t come close to overcoming combustion of fossil fuels, as pointed out in the 30 May 2013 issue of Nature Climate Change. Furthermore, forested ecosystems do not sequester additional carbon dioxide as it increases in the atmosphere, as disappointingly explained in the 6 August 2013 issue of New Phytologist.

Here’s the bottom line: On a planet 4 C hotter than baseline, all we can prepare for is human extinction (from Oliver Tickell’s 2008 synthesis in the Guardian).

John Davies concludes: “The world is probably at the start of a runaway Greenhouse Event which will end most human life on Earth before 2040.” He considers only atmospheric carbon dioxide concentration, not the many self-reinforcing feedback loops described below. 


Positive feedbacks
Positive feedbacks
Methane hydrates are bubbling out the Arctic Ocean (Science, March 2010). According to NASA’s CARVE project, these plumes were up to 150 kilometers across as of mid-July 2013. Whereas Malcolm Light’s 9 February 2012 forecast of extinction of all life on Earth by the middle of this century appears premature because his conclusion of exponential methane release during summer 2011 was based on data subsequently revised and smoothed by U.S. government agencies, subsequent information — most notably from NASA’s CARVE project — indicates the grave potential for catastrophic release of methane. Catastrophically rapid release of methane in the Arctic is further supported by Nafeez Ahmed’s thorough analysis in the 5 August 2013 issue of the Guardian as well as Natalia Shakhova’s 29 July 2013 interview with Nick Breeze (note the look of abject despair at the eight-minute mark).
Warm Atlantic water is defrosting the Arctic as it shoots through the Fram Strait (Science, January 2011).
Siberian methane vents have increased in size from less than a meter across in the summer of 2010 to about a kilometer across in 2011 (Tellus, February 2011)
Drought in the Amazon triggered the release of more carbon than the United States in 2010 (Science, February 2011). In addition, ongoing deforestation in the region is driving declines in precipitation at a rate much faster than long thought, as reported in the 19 July 2013 issue of Geophysical Research Letters.
Peat in the world’s boreal forests is decomposing at an astonishing rate (Nature Communications, November 2011)
Invasion of tall shrubs warms the soil, hence destabilizes the permafrost (Environmental Research Letters, March 2012)
Methane is being released from the Antarctic, too (Nature, August 2012). According to a paper in the 24 July 2013 issue of Scientific Reports, melt rate in the Antarctic has caught up to the Arctic.
Russian forest and bog fires are growing (NASA, August 2012), a phenomenon consequently apparent throughout the northern hemisphere (Nature Communications, July 2013). The New York Times reports hotter, drier conditions leading to huge fires in western North America as the “new normal” in their 1 July 2013 issue. A paper in the 22 July 2013 issue of the Proceedings of the National Academy of Sciences indicates boreal forests are burning at a rate exceeding that of the last 10,000 years.
Cracking of glaciers accelerates in the presence of increased carbon dioxide(Journal of Physics D: Applied Physics, October 2012)
The microbes have joined the party, too, according to a paper in the 23 February 2013 issue of New Scientist
Summer ice melt in Antarctica is at its highest level in a thousand years: Summer ice in the Antarctic is melting 10 times quicker than it was 600 years ago, with the most rapid melt occurring in the last 50 years (Nature Geoscience, April 2013). Although scientists have long expressed concern about the instability of the West Atlantic Ice Sheet (WAIS), a research paper published in the 28 August 2013 of Nature indicates the East Atlantic Ice Sheet (EAIS) has undergone rapid changes in the past five decades. The latter is the world’s largest ice sheet and was previously thought to be at little risk from climate change. But it has undergone rapid changes in the past five decades, signaling a potential threat to global sea levels. The EAIS holds enough water to raise sea levels more than 50 meters.
Surface meltwater draining through cracks in an ice sheet can warm the sheet from the inside, softening the ice and letting it flow faster, according to a study accepted for publication in the Journal of Geophysical Research: Earth Surface (July 2013). It appears a Heinrich Event has been triggered in Greenland. Consider the description of such an event as provided by Robert Scribbler on 8 August 2013:
In a Heinrich Event, the melt forces eventually reach a tipping point. The warmer water has greatly softened the ice sheet. Floods of water flow out beneath the ice. Ice ponds grow into great lakes that may spill out both over top of the ice and underneath it. Large ice damns (sic) may or may not start to form. All through this time ice motion and melt is accelerating. Finally, a major tipping point is reached and in a single large event or ongoing series of such events, a massive surge of water and ice flush outward as the ice sheet enters an entirely chaotic state. Tsunamis of melt water rush out bearing their vast floatillas (sic) of ice burgs (sic), greatly contributing to sea level rise. And that’s when the weather really starts to get nasty. In the case of Greenland, the firing line for such events is the entire North Atlantic and, ultimately the Northern Hemisphere.
Breakdown of the thermohaline conveyor belt is happening in the Antarctic as well as the Arctic, thus leading to melting of Antarctic permafrost (Scientific Reports, July 2013)
Loss of Arctic sea ice is reducing the temperature gradient between the poles and the equator, thus causing the jet stream to slow and meander. One result is the creation of weather blocks such as the recent very high temperatures in Alaska. As aresultboreal peat dries and catches fire like a coal seam. The resulting soot enters the atmosphere to fall again, coating the ice surface elsewhere, thus reducing albedo and hastening the melting of ice. Each of these individual phenomena has been reported, albeit rarely, but to my knowledge the dots have not been connected beyond this space. The inability or unwillingness of the media to connect two dots is not surprising, and has been routinely reported (recently including here with respect to climate change and wildfires) (July 2013)
Earthquakes trigger methane release, and consequent warming of the planet triggers earthquakes, as reported by Sam Carana at Arctic-news (October 2013)
Arctic drilling was fast-tracked by the Obama administration during the summer of 2012
Supertankers are taking advantage of the slushy Arctic, demonstrating that every catastrophe represents a business opportunity, as pointed out by Professor of journalism Michael I. Niman and picked up by Truthout (ArtVoice, September 2013)
As nearly as I can distinguish, only the latter feedback process is reversible at a temporal scale relevant to our species. Once you pull the tab on the can of beer, there’s no keeping the carbon dioxide from bubbling up and out. These feedbacks are not additive, they are multiplicative. Now that we’ve entered the era of expensive oil, I can’t imagine we’ll voluntarily terminate the process of drilling for oil and gas in the Arctic (or anywhere else). Nor will we willingly forgo a few dollars by failing to take advantage of the long-sought Northwest Passage.

Robin Westenra provides an assessment of these positive feedbacks at Seemorerocks on 14 July 2013. It’s worth a look.


Earth-system scientist Clive Hamilton concludes in his April 2013 book Earthmasters that “without [atmospheric sulphates associated with industrial activity] … Earth would be an extra 1.1 C warmer.” In other words, collapse takes us directly to 2 C within a matter of weeks. 

Several other academic scientists have concluded, in the refereed journal literature no less, that the 2 C mark is essentially impossible (for example, see the review paper by Mark New and colleagues published in the 29 November 2010 issue of the Philosophical Transactions of the Royal Society A). 

The German Institute for International and Security Affairs concluded 2 June 2013 that a 2 C rise in global-average temperature is no longer feasible (and Spiegel agrees, finally, in their 7 June 2013 issue), while the ultra-conservative International Energy Agency concludes that, “coal will nearly overtake oil as the dominant energy source by 2017 … without a major shift away from coal, average global temperatures could rise by 6 degrees Celsius by 2050, leading to devastating climate change.” 

Image from: The two epochs of Marcott, by Jos Hagelaars

At the 11:20 mark of this video, climate scientist Paul Beckwith indicates Earth could warm by 6 C within a decade. 

If you think his view is extreme, consider: 
  1. the 5 C rise in global-average temperature 55 million years ago during a span of 13 years (reported in the 1 October 2013 issue of Proceedings of the National Academy of Sciences); and also 
  2. the reconstruction of regional and global temperature for the past 11,300 years published in Science in March 2013. One result is shown in the above figure.

How Do We Act in the Face of Climate Chaos?

Below is a video of a recent presentation by Guy McPherson. 

Presentation by Guy McPherson in Boulder, Colorado on October 16, 2013.

Below are some extracts from the video, again slightly edited.

Malcolm Light in 2012 concluded, based on data from NOAA and NASA, that methane release had gone exponential and was leading to the demise of all life on Earth, not just human extinction, by the middle of the century.

So 3.5 C to 4 C is almost certainly a death sentence for all human beings on the planet, not because it'll be a warmer planet, but because the warming of the planet will remove all habitat for human beings. Ultimately we're human animals like other animals, we need habitat to survive.

Changes we see in three or four decades happen as a result of what we do today. There's a huge lag between our actions today in the consequences down the road in terms of the Earth's planetary systems.

Without plankton in the ocean, there goes roughly half the global food supply. The ability to lose land plants is growing rapidly and there goes the other half for the food supply for human beings. If we have up to 5 C by 2050, that'll certainly do the trick.

Why is this happening? It's civilization that drove us into population overshoot. We cannot go back anymore since 1939, since we invented nuclear armageddon. There's no going back. If we ceased the set of living arrangements at this point, the world's 400 or so nuclear power plants melt down catastrophically and we're all dead in a month. We cannot terminate industrial civilization until we decommission all nuclear power plants. It takes at least 20 years to decommission a nuclear power plant.

The bad news is that means that the world's four hundred or so nuclear power plants meltdown catastrophically in a short period of time. Fukushima represent a major threat to humanity. If they fail in moving the spent fuel rods next month, according to nuclear researcher Christina Consola, if one of those MOX fuel rods is exposed to the air, one of the 1565, it will kill 2.89 billion people on the planet in a matter of weeks, so nuclear catastrophe is right there on the horizon. 

People ask me: Why are you presenting this horrible information?

Action is the antidote to despair even if the action is hopeless. When a medical doctor knows that somebody has cancer, it's malpractice if they don't tell that. So I'm doing that. I think Bill McKibben and James Hansen and a whole bunch of climate scientists are guilty of malpractice. Because they know what I know. Almost every politician in the country knows what I know. All the leaders of the big banks know what I know. And they're lying to us.

I'm just presenting the information from other scientists here. I'm trying to the widest extent possible not to infuse my opinion in the situation. It's John Davies who on September 20, 2013, taking into account only carbon dioxide, says there will be few people left on the planet by 2040. It's Malcolm Light, writing in February 2012, who assesses the methane situation. And so on.

Yes, I agree with them, and that agreement is illustrated by me showing you that information.

I promote resistance against this omnicidal culture, not in the hope that it will save our species, but in the hope that it will save other species. Because as E.O. Wilson, biologist at Harvard, points out, it only takes 10 million years after a great extinction event, before you have a blossoming full rich planet again. That's what we're working toward. We're saving habitat for other species at this point.